The State Legislature Can't Choose Electors After an Election

The constitution says that the a electoral ballots from the states shall be and by the vice president in the presence of the house and the senate. So who counts them? Constitution was silent on that. And so congress, after a very bad experience in 18 76, passed the electoral count act, which specified procedures. It's a very poorly drafted act, but it's not terribly ambiguous about what will happen if the same party controls both houses. House ad end it would each break up, too, into its own chamber and vote on the slates of electors and come back and present those votes to the vice president, who has no deciding authority herself.